JPH03250442A - Magneto-optical disk recorder - Google Patents

Abstract

PURPOSE:To prevent data from being written on a medium under an abnormal state by executing the write test thereof with the aid of using a specified sector when a magneto-optical disk is inserted and reading out and verifying the sector. CONSTITUTION:When the medium 1 is inserted, a central control part 12 instructs a head control part 10 so as to move an optical head 3 to a specified track for executing the write test and respectively sets an external magnetic field set value for write test and a laser power set value to an external magnetic field set register 15 and a laser power set register 16. Then, the write operation of the data is executed with respect to the specified sector and the read operation thereof is executed with respect to the sector, next. Besides, the write data and the read data are compared. When the noncoincidence of the data is over a reference, alternate processing is executed with respect to the sector. Therefore, the abnormality of a device or the difference of characteristic between the device and the medium 1 are detected in advance and the data is prevented from being written on the medium 1 under the abnormal state.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a magneto-optical disk recording device that records and reproduces information on a magneto-optical disk in which data can be written, erased and retrieved in response to instructions from a host computer, and in particular, the present invention relates to a magneto-optical disk recording device that records and reproduces information on a magneto-optical disk in which data can be written, erased and retrieved. The present invention relates to a magneto-optical disk recording device having a function of automatically checking the compatibility with the disk at the time the disk is loaded.

[Conventional technology]

A magneto-optical disk has a perpendicularly magnetized film formed on a substrate, and records information by changing the direction of magnetization to the direction of the external magnetic field using an external perpendicular magnetic field and heat from a laser beam. FIG. 3 shows an example of the configuration of a magneto-optical disk (also referred to as a medium). Tracks 21 for recording and reproducing information on the magneto-optical disk are arranged spirally from the inner circumference, and information is continuously recorded on the tracks 21. Track numbers are sequentially assigned to the recording track 21 for each revolution, and the track is divided into a plurality of sectors including an ID section and a data section. In this case, the track 21 for one rotation is divided into 16 sectors,
A sector number from 1 to 16 is assigned to each sector. FIG. 4 shows an example of the structure of sectors. In the figure, one sector is divided into 10 parts 31 and a data part 32. In the 10th section 31, a track number and a sector number uniquely assigned to that sector are written. The data section 32 stores data that is read and written by an upper host computer. In the data section 32, information is stored based on the magnetization direction on the medium as described above, whereas in the 10th section 31, unevenness is provided on the medium, and information is read based on changes in light reflectance. Therefore, when a magneto-optical disk recording device reads information from a magneto-optical disk, there are two methods: one is to detect changes in the reflectance of light (the amount of reflected light), and the other is to detect the direction of magnetization based on the polarization angle of the reflected light. is switched between the 10 part 31 and the data part 32. Magneto-optical disks have a high defect rate because they are stored at extremely high density. Therefore, when a defective sector is detected, the data is substituted with another sector, thereby apparently reducing the probability that a sector defect will occur. When a magneto-optical disk recording device writes to a sector of a magneto-optical disk, it erases or erases that sector.
The process of writing and reading verification is executed three times. In the erasing process, the magnetization direction of the perpendicularly magnetized film on the magneto-optical disk substrate is aligned in the same direction over the entire sector. In the write process, the magnetization direction of the magnetic film is changed at the position where the information bit is "1" in the opposite direction to that during erasing. Therefore, when writing new data to a sector that has already been written, Erasing processing is essential.Between erasing and writing processing, the magneto-optical disk recording device reverses the direction of the external magnetic field.Read verification is performed to ensure that the sector in which data has been written does not contain defects exceeding a certain standard. This is done to check if a defective sector is detected in this process.
Alternative processing for writing the same data is performed again on empty sectors among the alternative sectors reserved in advance. Normally, a predetermined number of retry operations are performed before a sector is determined to be defective, which creates a problem in that the access time is increased in conjunction with access to an alternative sector. Furthermore, in the case of writing to a plurality of consecutive sectors, there is a problem in that if a plurality of defective sectors are detected, an access to a substitute sector occurs each time. Therefore, when writing and reading processes are performed using a disk that includes a large number of alternative sectors, processing efficiency decreases significantly compared to when a disk that does not have alternative sectors is used. Problems with the alternative processing include the following. (2) - Once the replaced sector has been replaced, it will not be checked again. (2) A sector may be determined to be defective not only due to a defect on the disk, but also due to poor adjustment of the magneto-optical disk recording device or a characteristic difference between the device and the disk. In particular, regarding (2), it is difficult to determine whether the disk is defective or the device is defective because it is difficult to know what kind of disk is being used due to the disk interchangeability of the magneto-optical disk recording device. Therefore, even if a good medium is read/written by a malfunctioning device, a large number of replaced sectors will be generated, resulting in a defective medium that takes a long time to write and read no matter what device it is used from now on. Therefore, conventionally, by reading the disc ID (disc characteristics, manufacturer name, etc.) written in a special pattern on the disc,
If the media is of a pre-registered type, it will not be processed as an abnormal media.

[Problem to be solved by the invention]

As mentioned above, in conventional magnetic disk recording devices,
By limiting the types of media, differences in compatibility between the device and the media are avoided, and there is a drawback that the media cannot be compatible with boat fishing. Also,
The device uses a self-diagnosis function to check its operation, but this does not include the disk, so if the device cannot read or write normally due to a failure that cannot be detected by the device's self-diagnosis, a large number of alternative sectors will be created. There was a problem with this. Therefore, it is an object of the present invention to provide a magneto-optical disk recording device that can solve this problem.

[Means to solve the problem]

In order to solve the above problems, the device of the present invention includes external magnetic field variable means (external magnetic field setting register 15, etc.) that can change the intensity of the external magnetic field applied to the magneto-optical disk (media 1, etc.) during r writing; A laser power variable means (laser power setting register 16, etc.) capable of changing the intensity of the write laser power; Means (central control 12 etc.).

[For use]

When a magneto-optical disk is inserted, a write test is performed on a trial basis using a specific sector that is not used by the user, and the sector is read and verified, thereby automatically performing a comprehensive check of the combination of the device and the media. On this occasion,
In order to check whether there is a margin for compatibility between the device and the media, a means for varying the intensity of the writing laser power and a means for varying the intensity of the external magnetic field are provided, and the setting value of the intensity is changed. do.

【Example】

The present invention will be explained in detail below based on FIGS. 1 to 4. FIG. 1 shows an embodiment of the configuration of a magneto-optical disk recording apparatus of the present invention. In the figure, a spindle motor 2 rotates a medium 1 as a magneto-optical disk at a constant speed. A motor driver 9 drives the spindle motor 2. The external magnetic field applying means 4 applies a magnetic field necessary for performing erasing and writing operations on the magneto-optical disk medium 1, and is driven by an external magnetic field driver 5. A drive signal to the external magnetic field driver 5 is output from the central control unit 12 during erase/write operations. The optical nodule 3 is driven by an optical head driver 6 to move over the medium 1 in the radial direction. Head control section 1
0 controls the optical head 3 to follow the track on the normal medium. The laser dry huff provides the optical head 3 with laser drive power necessary for erasing/writing operations on the medium 1, and is controlled by the central control unit 12. The binarization circuit 8 synchronizes with the data read out by the optical head 3 and converts it into binary data of 'O' and '1'. From this binary data, the rD detection section 11 detects the trunk number and sector number from the ID section 31 of the sector through which the optical head 3 is currently passing. The central control unit 12 identifies the current sector number read by the ID number detection unit 11 and performs a data read/write operation on the data section 32 within that sector. The head control section 10 receives an optical head movement request from the central control section 12, drives the optical head driver 6, and after the movement operation is completed, makes the optical head 3 stand still on the track. Also, since the track is in a spiral shape, the rD number detection unit II is monitored, and when it detects that it is on the last sector of the trunk, it performs key and 7-cut operations to return to the first sector of the same track again. conduct. The central control unit 12 is connected to the host computer 01 via the host computer interface 13. The host computer 01 specifies a track number and a sector number to the central control unit 12 and sequentially outputs/writes data. When the central control unit 12 receives a read/write instruction from the host computer 01, it sends a head movement instruction to the specified track to the head control unit 10. Then, after completing the head movement to the track, a subsequent write/write operation is performed for the designated sector. After the write operation is completed, the central control unit 12 performs a read operation on the sector written immediately before, as described above, and verifies the write data. In this verification operation, the read data is not sent to the host computer 01, but is compared with the write data in the sector buffer 14 by the central control unit 12. As a result of this comparison, if a data match (write error) exceeding the standard is found, the central control unit 12 executes alternative processing for that sector. An external magnetic setting register 15 and a laser power setting register 16 are added according to the present invention, and have certain set values during normal writing/reading. FIG. 2 is a flowchart showing the sequence of initial operations according to the present invention. It should be noted that the symbols 31 to S7 below indicate steps in the figure. The central control unit 12 waits until the medium 1 is inserted (Sl). When the medium is inserted, the central control unit 12 causes the head control unit 10 to move the optical head 3 to a specific track for performing a write test.
(S2). The external magnetic field setting value and laser power setting value for the write test are set in the external magnetic field setting register 16 and the laser power setting register F, respectively (S3), and a write operation is performed for the specific sector (S4). The data reading operation is continued for that sector (S5). Next, the written data and the read data are compared, and it is determined whether the data mismatch (error) exceeds the standard (S6). If the standard is exceeded, it is treated as a device and media matching error.
It enters an error state and does not accept normal write/read operations (S7). If the error is below the standard, it is considered to be a normal state, the external magnetic field setting value and the laser power setting value are set to normal values (S8), and the system enters a standby state for accepting further write/read operations. (S9).

【Effect of the invention】

According to the present invention, before actually writing data to a magneto-optical disk, a write test is automatically performed by tightening the write conditions for a specific sector, so there is no problem with the device and the media. Difference in characteristics (consistency) with
can be detected in advance. Therefore, it is possible to prevent writing to the medium in an abnormal state, and therefore it is possible to prevent alternative processing that is not caused by a defect in the medium, such as the generation of many alternative sectors in a good medium.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention, FIG. 2 is a flowchart of a sequence for testing the compatibility between the device and the media, which is the main operation of FIG. 1, and FIG. 3 is the configuration of the media. Figure 4 shows an example of a sector configuration. 01: host computer, 1: media, 2 spindle motor, 3: optical head, 4: external magnetic field applying means, 5: external magnetic field driver, 6: optical head driver, 7: laser driver, 8: binarization circuit, 9: Mode driver, 10: Head control section, 11: ID number detection section, 12: Central control section,
13: Upper computer interface, 14: Sector buffer, 15: External magnetic field setting register, 16: Laser power setting register, 21: 1! Kuv 16 Figure 3 Figure 4

Claims (1)

[Scope of Claims] 1) An external magnetic field variable means that can change the intensity of the external magnetic field applied to the magneto-optical disk during writing, a laser power variable means that can change the intensity of the write laser power, and a magneto-optical disk is inserted. At that point, a write test is performed on a predetermined sector by lowering or increasing the intensity of the external magnetic field and the write laser power to predetermined levels through the external magnetic field variable means and the laser power variable means, respectively. 1. A magneto-optical disk recording device comprising means for checking compatibility with a magneto-optical disk with a predetermined margin.